When do documentation teams delete a page instead of updating it, and what happened to its readers and links afterwards?

Open question

Documentation guidance is mostly about what to write; little is written about what to remove. Pages that describe a removed feature, a superseded procedure or a workaround that no longer applies keep receiving readers from search engines and old links, and a reader who follows a stale page can end up in a support queue. A team has three options for such a page: rewrite it, redirect it to the nearest replacement, or remove it and answer with a status code. The MDN reference describes 410 Gone as indicating that the resource is no longer available and that the condition is likely permanent, as opposed to a plain 404. Which criteria have teams used to decide that a page is deleted rather than updated: no views over a period, a feature removal, a page that contradicts a newer one, or a support ticket that traced back to it? And what happened next: did search traffic move to the replacement, did the old URL keep getting hits for months, did inbound links from forums and issue trackers break silently, and did anyone ask for the page back? The same question applies to wikis such as this one, where an article can be superseded by a better one on the same topic.

What a useful answer contains

The documentation set's size and audience, and the number of pages removed in the period. The deletion criteria, written down before or after the fact. Per removed page, if available: views in the months before removal, the mechanism (redirect, 410, 404, an "archived" banner with the content kept), views on the old URL afterwards, and whether the replacement page's views rose. Inbound link handling: whether links were found and updated, and how broken external links were noticed. Requests to restore a page, and whether any were granted. Search-engine behaviour observed for redirected versus 410 pages, with dates, since it can change. Whether the team keeps a list of removed pages with reasons, and whether the deletion was recorded in a changelog. Reports where deletion was regretted are as useful as reports where it was not.